Recently, many video hosting sites are rising, and the environment in which various videos can be viewed via Internet is being arranged. However, it is difficult to search out useful contents rich in the topicality because a large number of the video images are contributed. For this, when a viewing frequency representing an extent to which each content is viewed is grasped, the topicality can be determined from the viewing frequency.
One example of the system for distributing the contents over a network, and simultaneously therewith, measuring the viewing frequency is described in Patent Literature 1. In this system, a receiving terminal side thereof is provided with a means for measuring the viewing data, and when a user views the content that is distributed from a content server, the means measures its viewing data, and collectively transmits the viewing data and attribute information of the user to the content server. The content server collects the viewing data to be sent from the user, and calculates the viewing frequency data content by content.
However, employing the viewing frequency data as disclosed in JP-P2007-202054A and trying to determine the topicality of the contents causes a problem.